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2018_01_23_sba-l88-sba_167 | by dsearls
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2018_01_23_sba-l88-sba_167

The San Andreas Fault, here exposed on the floor of the Carrizo Plain in one of the most desolate and least-visited regions of California. Note the offset streams cutting across the fault. On the far side is the Pacific plate and on the near side the North American. It's a right-lateral fault, meaning the other side of it is moving to the right, on whichever side you stand. The Pacific side is moving to the northwest in a motion geologists call "right step." Streams that once flowed straight across the fault now step to the right before they continue. These steps are recent. The plate below has moved hundreds of miles in the last two dozen million years. One study says stream channels were offset up to 50 feet in the 1857 Fort Tejon quake, one of the largest in historic time. This section of the fault raises the Elkhorn Scarp through the Elkhorn Hills. The most spine-like segment is also called Dragon's Back

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Taken on January 23, 2018